diff --git a/src-tauri/Cargo.toml b/src-tauri/Cargo.toml
index a370575..5b1d18c 100644
--- a/src-tauri/Cargo.toml
+++ b/src-tauri/Cargo.toml
@@ -10,5 +10,8 @@ rust-version = "1.77"
 tauri-build = { version = "2", features = [] }
 
 [dependencies]
+serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 tauri = { version = "2", features = [] }
+tauri-plugin-dialog = "2"
+tauri-plugin-opener = "2"
diff --git a/src-tauri/capabilities/default.json b/src-tauri/capabilities/default.json
index 0392774..d3e2a08 100644
--- a/src-tauri/capabilities/default.json
+++ b/src-tauri/capabilities/default.json
@@ -2,5 +2,11 @@
   "identifier": "default",
   "description": "Default capability for the Heimgeist Tauri migration spike.",
   "windows": ["main"],
-  "permissions": ["core:default"]
+  "permissions": [
+    "core:default",
+    "dialog:allow-open",
+    "opener:allow-default-urls",
+    "opener:allow-open-path",
+    "opener:allow-open-url"
+  ]
 }
diff --git a/src-tauri/src/main.rs b/src-tauri/src/main.rs
index c6aa44e..efb4ebf 100644
--- a/src-tauri/src/main.rs
+++ b/src-tauri/src/main.rs
@@ -1,28 +1,273 @@
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]
 
-use std::{collections::HashMap, sync::Mutex};
+use std::{
+    fs,
+    path::PathBuf,
+    sync::Mutex,
+};
 
-use serde_json::{json, Value};
-use tauri::State;
+use serde::Deserialize;
+use serde_json::{json, Map, Value};
+use tauri::{AppHandle, Emitter, Manager, State, WindowEvent};
+use tauri_plugin_dialog::DialogExt;
+use tauri_plugin_opener::OpenerExt;
 
-type SettingsStore = Mutex<HashMap<String, Value>>;
+const DEFAULT_BACKEND_API_URL: &str = "http://127.0.0.1:8000";
+const DEFAULT_OLLAMA_API_URL: &str = "http://127.0.0.1:11434";
+const DEFAULT_EMBED_MODEL: &str = "nomic-embed-text:latest";
+const DEFAULT_TRANSCRIPTION_MODEL: &str = "base";
+const BGE_EMBED_MODEL: &str = "bge-m3:latest";
+const DEFAULT_UI_SCALE: f64 = 1.0;
+const MIN_UI_SCALE: f64 = 0.7;
+const MAX_UI_SCALE: f64 = 1.3;
+const SETTINGS_FILE_NAME: &str = "settings.json";
+const CHANGELOG_PAGE_SIZE: u64 = 50;
 
-fn default_settings() -> HashMap<String, Value> {
-    HashMap::from([
-        ("backendApiUrl".into(), json!("http://127.0.0.1:8000")),
-        ("ollamaApiUrl".into(), json!("http://127.0.0.1:11434")),
-        ("chatModel".into(), json!("llama3")),
-        ("visionModel".into(), json!("")),
-        ("embedModel".into(), json!("nomic-embed-text:latest")),
-        ("rerankModel".into(), json!("nomic-embed-text:latest")),
-        ("transcriptionModel".into(), json!("base")),
-        ("colorScheme".into(), json!("Default")),
-        ("uiScale".into(), json!(1)),
-        ("openDevToolsOnStartup".into(), json!(false)),
-        ("audioInputEnabled".into(), json!(true)),
-        ("audioInputDeviceId".into(), json!("")),
-        ("audioInputLanguage".into(), json!("")),
-    ])
+type SettingsMap = Map<String, Value>;
+
+struct SettingsStore {
+    path: PathBuf,
+    settings: Mutex<SettingsMap>,
+}
+
+#[derive(Debug, Deserialize)]
+struct PickPathsOptions {
+    title: Option<String>,
+    filters: Option<Vec<DialogFilter>>,
+    multiple: Option<bool>,
+}
+
+#[derive(Debug, Deserialize)]
+struct DialogFilter {
+    name: Option<String>,
+    extensions: Option<Vec<String>>,
+}
+
+fn default_settings() -> SettingsMap {
+    let mut settings = SettingsMap::new();
+    settings.insert("backendApiUrl".into(), json!(DEFAULT_BACKEND_API_URL));
+    settings.insert("ollamaApiUrl".into(), json!(DEFAULT_OLLAMA_API_URL));
+    settings.insert("chatModel".into(), json!("llama3"));
+    settings.insert("visionModel".into(), json!(""));
+    settings.insert("embedModel".into(), json!(DEFAULT_EMBED_MODEL));
+    settings.insert("rerankModel".into(), json!(DEFAULT_EMBED_MODEL));
+    settings.insert("transcriptionModel".into(), json!(DEFAULT_TRANSCRIPTION_MODEL));
+    settings.insert("colorScheme".into(), json!("Default"));
+    settings.insert("uiScale".into(), json!(DEFAULT_UI_SCALE));
+    settings.insert("openDevToolsOnStartup".into(), json!(false));
+    settings.insert("audioInputEnabled".into(), json!(true));
+    settings.insert("audioInputDeviceId".into(), json!(""));
+    settings.insert("audioInputLanguage".into(), json!(""));
+    settings
+}
+
+fn value_to_trimmed_string(value: Option<&Value>) -> String {
+    match value {
+        Some(Value::String(text)) => text.trim().to_string(),
+        Some(Value::Number(number)) => number.to_string(),
+        Some(Value::Bool(value)) => value.to_string(),
+        _ => String::new(),
+    }
+}
+
+fn value_to_number(value: Option<&Value>) -> Option<f64> {
+    match value {
+        Some(Value::Number(number)) => number.as_f64(),
+        Some(Value::String(text)) => text.trim().parse::<f64>().ok(),
+        _ => None,
+    }
+}
+
+fn normalize_ui_scale(value: Option<&Value>) -> f64 {
+    let scale = value_to_number(value).unwrap_or(DEFAULT_UI_SCALE);
+    let clamped = scale.clamp(MIN_UI_SCALE, MAX_UI_SCALE);
+    (clamped * 100.0).round() / 100.0
+}
+
+fn normalize_boolean_setting(value: Option<&Value>) -> bool {
+    match value {
+        Some(Value::String(text)) => match text.trim().to_lowercase().as_str() {
+            "true" | "1" | "yes" | "on" => true,
+            "false" | "0" | "no" | "off" | "" => false,
+            _ => false,
+        },
+        Some(Value::Bool(value)) => *value,
+        _ => false,
+    }
+}
+
+fn normalize_model_name(value: Option<&Value>, fallback: &str) -> String {
+    let trimmed = value_to_trimmed_string(value);
+    if trimmed.is_empty() {
+        fallback.to_string()
+    } else {
+        trimmed
+    }
+}
+
+fn normalize_embed_model(value: Option<&Value>) -> String {
+    let trimmed = value_to_trimmed_string(value);
+    if trimmed.is_empty() {
+        return DEFAULT_EMBED_MODEL.to_string();
+    }
+
+    match trimmed.to_lowercase().as_str() {
+        "bge" | "bge-m3" | BGE_EMBED_MODEL => BGE_EMBED_MODEL.to_string(),
+        "nomic" | "nomic-embed-text" | DEFAULT_EMBED_MODEL => DEFAULT_EMBED_MODEL.to_string(),
+        _ => trimmed,
+    }
+}
+
+fn looks_like_ollama_url(value: &str) -> bool {
+    tauri::Url::parse(value)
+        .map(|parsed| {
+            parsed.port() == Some(11434)
+                || parsed.path().trim_end_matches('/').eq_ignore_ascii_case("/api")
+        })
+        .unwrap_or(false)
+}
+
+fn migrate_settings(source: Option<SettingsMap>) -> (SettingsMap, bool) {
+    let source = source.unwrap_or_default();
+    let mut next = default_settings();
+    let mut migrated = false;
+
+    for (key, value) in source.iter() {
+        next.insert(key.clone(), value.clone());
+    }
+
+    if !source.contains_key("backendApiUrl") {
+        if let Some(Value::String(ollama_api_url)) = source.get("ollamaApiUrl") {
+            if looks_like_ollama_url(ollama_api_url) {
+                next.insert("backendApiUrl".into(), json!(DEFAULT_BACKEND_API_URL));
+                next.insert("ollamaApiUrl".into(), json!(ollama_api_url.trim()));
+            } else {
+                next.insert("backendApiUrl".into(), json!(ollama_api_url.trim()));
+                next.insert("ollamaApiUrl".into(), json!(DEFAULT_OLLAMA_API_URL));
+            }
+            migrated = true;
+        }
+    }
+
+    if !source.contains_key("openDevToolsOnStartup") {
+        migrated = true;
+    }
+
+    if !source.contains_key("rerankModel") {
+        let embed_model = next
+            .get("embedModel")
+            .cloned()
+            .unwrap_or_else(|| json!(DEFAULT_EMBED_MODEL));
+        next.insert("rerankModel".into(), embed_model);
+        migrated = true;
+    }
+
+    if !source.contains_key("visionModel") {
+        let chat_model = value_to_trimmed_string(next.get("chatModel"));
+        next.insert("visionModel".into(), json!(chat_model));
+        migrated = true;
+    }
+
+    if !source.contains_key("transcriptionModel") {
+        next.insert("transcriptionModel".into(), json!(DEFAULT_TRANSCRIPTION_MODEL));
+        migrated = true;
+    }
+
+    normalize_settings(&mut next);
+    (next, migrated)
+}
+
+fn normalize_settings(settings: &mut SettingsMap) {
+    let backend_api_url = value_to_trimmed_string(settings.get("backendApiUrl"));
+    let ollama_api_url = value_to_trimmed_string(settings.get("ollamaApiUrl"));
+    let chat_model = normalize_model_name(settings.get("chatModel"), "");
+    let vision_model = normalize_model_name(settings.get("visionModel"), "");
+    let embed_model = normalize_embed_model(settings.get("embedModel"));
+    let rerank_model = normalize_embed_model(settings.get("rerankModel"));
+    let transcription_model =
+        normalize_model_name(settings.get("transcriptionModel"), DEFAULT_TRANSCRIPTION_MODEL);
+    let ui_scale = normalize_ui_scale(settings.get("uiScale"));
+    let open_devtools_on_startup =
+        normalize_boolean_setting(settings.get("openDevToolsOnStartup"));
+    let audio_input_enabled = normalize_boolean_setting(settings.get("audioInputEnabled"));
+    let audio_input_device_id = value_to_trimmed_string(settings.get("audioInputDeviceId"));
+    let audio_input_language =
+        value_to_trimmed_string(settings.get("audioInputLanguage")).to_lowercase();
+
+    settings.insert("backendApiUrl".into(), json!(backend_api_url));
+    settings.insert("ollamaApiUrl".into(), json!(ollama_api_url));
+    settings.insert("chatModel".into(), json!(chat_model));
+    settings.insert("visionModel".into(), json!(vision_model));
+    settings.insert("embedModel".into(), json!(embed_model));
+    settings.insert("rerankModel".into(), json!(rerank_model));
+    settings.insert("transcriptionModel".into(), json!(transcription_model));
+    settings.insert("uiScale".into(), json!(ui_scale));
+    settings.insert("openDevToolsOnStartup".into(), json!(open_devtools_on_startup));
+    settings.insert("audioInputEnabled".into(), json!(audio_input_enabled));
+    settings.insert("audioInputDeviceId".into(), json!(audio_input_device_id));
+    settings.insert("audioInputLanguage".into(), json!(audio_input_language));
+}
+
+fn settings_file_path(app: &AppHandle) -> Result<PathBuf, String> {
+    if let Ok(path) = std::env::var("HEIMGEIST_SETTINGS_FILE") {
+        let trimmed = path.trim();
+        if !trimmed.is_empty() {
+            return Ok(PathBuf::from(trimmed));
+        }
+    }
+
+    app.path()
+        .app_config_dir()
+        .map(|dir| dir.join(SETTINGS_FILE_NAME))
+        .map_err(|error| format!("Could not resolve Tauri settings path: {error}"))
+}
+
+fn read_settings_file(path: &PathBuf) -> Result<Option<SettingsMap>, String> {
+    if !path.exists() {
+        return Ok(None);
+    }
+
+    let data = fs::read_to_string(path)
+        .map_err(|error| format!("Could not read settings from {}: {error}", path.display()))?;
+    let value: Value = serde_json::from_str(&data)
+        .map_err(|error| format!("Could not parse settings from {}: {error}", path.display()))?;
+
+    match value {
+        Value::Object(settings) => Ok(Some(settings)),
+        _ => Ok(None),
+    }
+}
+
+fn write_settings_file(path: &PathBuf, settings: &SettingsMap) -> Result<(), String> {
+    if let Some(parent) = path.parent() {
+        fs::create_dir_all(parent).map_err(|error| {
+            format!(
+                "Could not create settings directory {}: {error}",
+                parent.display()
+            )
+        })?;
+    }
+
+    let data = serde_json::to_string_pretty(settings)
+        .map_err(|error| format!("Could not serialize settings: {error}"))?;
+    fs::write(path, format!("{data}\n"))
+        .map_err(|error| format!("Could not write settings to {}: {error}", path.display()))
+}
+
+fn load_settings_store(app: &AppHandle) -> Result<SettingsStore, String> {
+    let path = settings_file_path(app)?;
+    let raw_settings = read_settings_file(&path)?;
+    let should_write = raw_settings.is_none();
+    let (settings, migrated) = migrate_settings(raw_settings);
+
+    if should_write || migrated {
+        write_settings_file(&path, &settings)?;
+    }
+
+    Ok(SettingsStore {
+        path,
+        settings: Mutex::new(settings),
+    })
 }
 
 fn unavailable_update_status(message: &str) -> Value {
@@ -37,77 +282,173 @@ fn unavailable_update_status(message: &str) -> Value {
     })
 }
 
+fn normalize_changelog_page(page: Option<u64>) -> u64 {
+    page.filter(|value| *value > 0).unwrap_or(1)
+}
+
 #[tauri::command]
-fn get_settings(settings: State<'_, SettingsStore>) -> Result<Value, String> {
-    let settings = settings
+fn get_settings(store: State<'_, SettingsStore>) -> Result<Value, String> {
+    let settings = store
+        .settings
         .lock()
         .map_err(|_| "Settings store is unavailable.".to_string())?;
-    Ok(json!(settings.clone()))
+    Ok(Value::Object(settings.clone()))
 }
 
 #[tauri::command]
 fn set_setting(
     key: String,
     value: Value,
-    settings: State<'_, SettingsStore>,
+    store: State<'_, SettingsStore>,
 ) -> Result<bool, String> {
-    let mut settings = settings
+    let mut settings = store
+        .settings
         .lock()
         .map_err(|_| "Settings store is unavailable.".to_string())?;
     settings.insert(key, value);
+    normalize_settings(&mut settings);
+    write_settings_file(&store.path, &settings)?;
     Ok(true)
 }
 
 #[tauri::command]
 fn update_settings(
-    settings: HashMap<String, Value>,
+    settings: SettingsMap,
     store: State<'_, SettingsStore>,
 ) -> Result<bool, String> {
-    let mut store = store
+    let mut current_settings = store
+        .settings
         .lock()
         .map_err(|_| "Settings store is unavailable.".to_string())?;
-    store.extend(settings);
+    current_settings.extend(settings);
+    normalize_settings(&mut current_settings);
+    write_settings_file(&store.path, &current_settings)?;
     Ok(true)
 }
 
 #[tauri::command]
 fn get_update_status() -> Value {
-    unavailable_update_status("Tauri update checks are not implemented in this migration spike.")
+    unavailable_update_status("Tauri update checks are not implemented in this migration phase.")
 }
 
 #[tauri::command]
 fn check_for_updates() -> Value {
-    unavailable_update_status("Tauri update checks are not implemented in this migration spike.")
+    unavailable_update_status("Tauri update checks are not implemented in this migration phase.")
 }
 
 #[tauri::command]
 fn get_changelog_page(page: Option<u64>) -> Value {
     json!({
-        "page": page.unwrap_or(1),
-        "pageSize": 50,
+        "page": normalize_changelog_page(page),
+        "pageSize": CHANGELOG_PAGE_SIZE,
         "hasMore": false,
         "entries": []
     })
 }
 
 #[tauri::command]
-fn pick_paths(_options: Option<Value>) -> Vec<String> {
-    Vec::new()
+async fn pick_paths(app: AppHandle, options: Option<PickPathsOptions>) -> Result<Vec<String>, String> {
+    let options = options.unwrap_or(PickPathsOptions {
+        title: None,
+        filters: None,
+        multiple: None,
+    });
+    let mut dialog = app.dialog().file();
+
+    if let Some(title) = options.title.as_deref().map(str::trim).filter(|title| !title.is_empty()) {
+        dialog = dialog.set_title(title);
+    }
+
+    for filter in options.filters.unwrap_or_default() {
+        let name = filter
+            .name
+            .as_deref()
+            .map(str::trim)
+            .filter(|name| !name.is_empty())
+            .unwrap_or("Files")
+            .to_string();
+        let extensions: Vec<String> = filter
+            .extensions
+            .unwrap_or_default()
+            .into_iter()
+            .map(|extension| extension.trim().trim_start_matches('.').to_string())
+            .filter(|extension| !extension.is_empty())
+            .collect();
+
+        if !extensions.is_empty() {
+            let extension_refs: Vec<&str> = extensions.iter().map(String::as_str).collect();
+            dialog = dialog.add_filter(name, &extension_refs);
+        }
+    }
+
+    let paths = if options.multiple.unwrap_or(true) {
+        dialog.blocking_pick_files().unwrap_or_default()
+    } else {
+        dialog.blocking_pick_file().into_iter().collect()
+    };
+
+    paths
+        .into_iter()
+        .map(|path| {
+            path.into_path()
+                .map(|path| path.to_string_lossy().into_owned())
+                .map_err(|error| format!("Could not resolve selected file path: {error}"))
+        })
+        .collect()
 }
 
 #[tauri::command]
-fn open_path(_file_path: String) -> bool {
-    false
+fn open_path(app: AppHandle, file_path: String) -> Result<bool, String> {
+    let file_path = file_path.trim();
+    if file_path.is_empty() {
+        return Ok(false);
+    }
+
+    match app.opener().open_path(file_path, None::<&str>) {
+        Ok(_) => Ok(true),
+        Err(error) => {
+            eprintln!("Failed to open path {file_path}: {error}");
+            Ok(false)
+        }
+    }
+}
+
+fn is_allowed_external_url(url: &str) -> bool {
+    tauri::Url::parse(url)
+        .map(|parsed| matches!(parsed.scheme(), "http" | "https" | "mailto" | "tel"))
+        .unwrap_or(false)
 }
 
 #[tauri::command]
-fn open_external_link(_url: String) -> bool {
-    false
+fn open_external_link(app: AppHandle, url: String) -> Result<bool, String> {
+    let url = url.trim();
+    if url.is_empty() || !is_allowed_external_url(url) {
+        return Ok(false);
+    }
+
+    match app.opener().open_url(url, None::<&str>) {
+        Ok(_) => Ok(true),
+        Err(error) => {
+            eprintln!("Failed to open URL {url}: {error}");
+            Ok(false)
+        }
+    }
 }
 
 fn main() {
     tauri::Builder::default()
-        .manage(Mutex::new(default_settings()))
+        .plugin(tauri_plugin_dialog::init())
+        .plugin(tauri_plugin_opener::init())
+        .setup(|app| {
+            let store = load_settings_store(app.handle()).map_err(std::io::Error::other)?;
+            app.manage(store);
+            Ok(())
+        })
+        .on_window_event(|window, event| {
+            if matches!(event, WindowEvent::Focused(true)) {
+                let _ = window.emit("window-focused", ());
+            }
+        })
         .invoke_handler(tauri::generate_handler![
             get_settings,
             set_setting,
diff --git a/src/desktop/desktopApi.js b/src/desktop/desktopApi.js
index 9623057..774378b 100644
--- a/src/desktop/desktopApi.js
+++ b/src/desktop/desktopApi.js
@@ -27,6 +27,8 @@ const DEFAULT_UPDATE_STATUS = Object.freeze({
 const hasWindow = () => typeof window !== 'undefined'
 const getElectronApi = () => (hasWindow() ? window.electronAPI : undefined)
 const getTauriCore = () => (hasWindow() ? window.__TAURI__?.core : undefined)
+const getTauriEvent = () => (hasWindow() ? window.__TAURI__?.event : undefined)
+const tauriWindowFocusUnlisteners = new WeakMap()
 
 function callElectronApi(methodName, ...args) {
   const method = getElectronApi()?.[methodName]
@@ -77,6 +79,32 @@ function getExternalUrl(eventOrUrl) {
   return eventOrUrl?.currentTarget?.href || eventOrUrl?.target?.href || ''
 }
 
+function listenForTauriWindowFocus(callback) {
+  const listen = getTauriEvent()?.listen
+  if (typeof listen !== 'function') {
+    return undefined
+  }
+
+  const unlistenPromise = listen('window-focused', () => callback())
+  tauriWindowFocusUnlisteners.set(callback, unlistenPromise)
+  return unlistenPromise
+}
+
+function unlistenForTauriWindowFocus(callback) {
+  const unlistenPromise = tauriWindowFocusUnlisteners.get(callback)
+  if (!unlistenPromise) {
+    return undefined
+  }
+
+  tauriWindowFocusUnlisteners.delete(callback)
+  Promise.resolve(unlistenPromise).then((unlisten) => {
+    if (typeof unlisten === 'function') {
+      unlisten()
+    }
+  })
+  return unlistenPromise
+}
+
 const desktopApi = {
   getSettings: () => resultOrFallback(
     callElectronApi('getSettings') ?? callTauriCommand('get_settings'),
@@ -120,8 +148,8 @@ const desktopApi = {
     const url = getExternalUrl(eventOrUrl)
     return resultOrFallback(callTauriCommand('open_external_link', { url }), false)
   },
-  onWindowFocus: (callback) => callElectronApi('onWindowFocus', callback),
-  offWindowFocus: (callback) => callElectronApi('offWindowFocus', callback),
+  onWindowFocus: (callback) => callElectronApi('onWindowFocus', callback) ?? listenForTauriWindowFocus(callback),
+  offWindowFocus: (callback) => callElectronApi('offWindowFocus', callback) ?? unlistenForTauriWindowFocus(callback),
 }
 
 export default desktopApi